v4.19.13 snapshot.
diff --git a/drivers/char/tpm/eventlog/efi.c b/drivers/char/tpm/eventlog/efi.c
new file mode 100644
index 0000000..3e673ab
--- /dev/null
+++ b/drivers/char/tpm/eventlog/efi.c
@@ -0,0 +1,66 @@
+/*
+ * Copyright (C) 2017 Google
+ *
+ * Authors:
+ * Thiebaud Weksteen <tweek@google.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <linux/efi.h>
+#include <linux/tpm_eventlog.h>
+
+#include "../tpm.h"
+#include "common.h"
+
+/* read binary bios log from EFI configuration table */
+int tpm_read_log_efi(struct tpm_chip *chip)
+{
+
+ struct linux_efi_tpm_eventlog *log_tbl;
+ struct tpm_bios_log *log;
+ u32 log_size;
+ u8 tpm_log_version;
+
+ if (!(chip->flags & TPM_CHIP_FLAG_TPM2))
+ return -ENODEV;
+
+ if (efi.tpm_log == EFI_INVALID_TABLE_ADDR)
+ return -ENODEV;
+
+ log = &chip->log;
+
+ log_tbl = memremap(efi.tpm_log, sizeof(*log_tbl), MEMREMAP_WB);
+ if (!log_tbl) {
+ pr_err("Could not map UEFI TPM log table !\n");
+ return -ENOMEM;
+ }
+
+ log_size = log_tbl->size;
+ memunmap(log_tbl);
+
+ log_tbl = memremap(efi.tpm_log, sizeof(*log_tbl) + log_size,
+ MEMREMAP_WB);
+ if (!log_tbl) {
+ pr_err("Could not map UEFI TPM log table payload!\n");
+ return -ENOMEM;
+ }
+
+ /* malloc EventLog space */
+ log->bios_event_log = kmemdup(log_tbl->log, log_size, GFP_KERNEL);
+ if (!log->bios_event_log)
+ goto err_memunmap;
+ log->bios_event_log_end = log->bios_event_log + log_size;
+
+ tpm_log_version = log_tbl->version;
+ memunmap(log_tbl);
+ return tpm_log_version;
+
+err_memunmap:
+ memunmap(log_tbl);
+ return -ENOMEM;
+}